Power press and the like



May 8, 1934.

J. A. T. NA PIER POWER PRESS AND THE LIKE Filed Ju ly 15. 1933 INVENTOR BY 1W; W

NNGRW an ATTORN EYS Patented May 8, 1934 UNETE ATES PA ET FFICE POVER PRESS AND THE LIKE England Application July 15, 1933, Serial No. 630,519 In Great Britain Juiy 22, 1932 1 Claim.

This invention relates to power presses and the like and has for its object to provide an improved safety device designed to prevent the hand of the operator of the press from being accidentally injured by the operation of the press.

The improved safety device according to our present invention comprises the combination with a movable guard which in the safety position completely surrounds the bolster or operating plate of the machine, of a trigger or the like projection on the operating rod, a carrier supporting the guard, a radius rod or similar contact member on the carrier arranged to engage the'trigger on the operating rod and prevent the movement of the latter while the guard is in any position other than the safety position, and a notch or recess in the radius rod arranged so as to clear the trigger and allow the operating rod to be moved into operative position only when the movable guard is in its safety position.

An arrangement embodying the invention as applied to an ordinary power-operated press is illustrated in the accompanying drawing, in which Fig. l is a perspective and mainly diagrammatic View of the safety device according to the invention in the inoperative position;

Fig. 2 is a similar View of the safety device in the operative or safety position.

Referring to the drawing the movable guard 1 is in the form of a galvanized wire gauze or mesh structure provided with two handles 2 on the front side adapted to be easily seized by the operator of the press.

The guard is fixed upon the free end of a carrier-bar 3 which is pivoted at 4 to the cheek 5 of the machine so as to allow the guard 4 to be raised or lowered as required. The carrier-bar 3 is extended beyond its fulcrum 4 to form the extension 6 which carries a counter-balance weight 7 adapted to automatically swing the guard up into and retain it in the inoperative position shown in Fig. 1 when the handles 2 are released by the operator, for instance when the press is *5 not required to be operated. This action may also be assisted by tensile springs such as that shown Rigidly attached to the carrier-bar 3 is a radius-link 9 which as the carrier-bar is moved upon its fulcrum 4 abuts continuously against, or remains in the path of, a trigger or the like projection 10 fixed to the operating push or pullrod 11 whereby the press is operated, so that the 5 said push or pull-rod 11 cannot be moved to operate the press so long as the radius-link 9 abuts against the trigger 10.

A notch or recess 12 is provided in the radiuslink 9 in such a position that the said notch comes into alignment with the trigger 10 only when the movable guard 1 upon the carrier-bar 3 is moved into its operative and safety position shown in Fig. 2, in which position the guard 1 practically surrounds the bolster 13 of the press and excludes the possibility of the operators hand being in contact therewith. 0n the guard 1 coming into this position the notch or recess 12 releases the trigger 10 and thus enables the operator to move the push or pull-rod 11 by means of the usual treadle (not shown) to operate the press.

On the operator releasing the treadle while retaining the guard 1 in its operative position the push or pull-rod 11 returns to its normal inoperative position in which the trigger l0 disengages from the notch 12 in the radius link 9. The handles 2 of the guard l are now released by the operator whereupon the counter-balance weight '7 and spring 3 automatically raise the guard 1 to its inoperative position shown in Fig. 1, and at the same time move the radius-link 9 into the position in which it abuts against the trigger 10 on the push or pull-rod 11 so that the machine cannot again be operated unless and until the operator again moves the guard 1 into the operative position shown in Fig. 2 in which the guard covers the bolster 13 of the press as referred to above.

The safety device is so constructed that until the guard 1 rests on the bolster 13 of the press the trigger 10 on the push or pull-rod 11 will not pass into the notch or recess 12 in the radius-link 9. This means that if a hand of the operator is between the bolster 13 and the bottom of the guard 1 no engagement between the push or pullrod 11 and radius-link 9 can be made and the press will not operate, irrespective of the operator trying to move the foot treadle, as the push or pull-rod 11 is held solid until the correct alignment is obtained.

The counter-balance weight 7 lifts the guard into the open position immediately when the operator releases the handles 2 of the guard and thus prevents the machine operating.

The invention is not restricted to the precise details given in the above description and shown 05 in the drawing, as certain of these might easily be varied without affecting the desired result of the safety device. For instance the guard 1 may be made in any other form which will serve the same purpose and of any other material than 110 wire gauze. Also the guard might be so arranged as to have a straight up and down guided movement with a pivotal or sliding connection with the end or other part of the carrier-bar 3, and this bar and the radius-link 9 might assume other forms than those shown; for instance the radiuslink might easily be made as an integral part of the carrier-bar.

What I claim and desire to secure by Letters Patent is:-

In a power press, in combination, a guard device adapted to swing up and down upon a pivot and to surround the operating plate of the machine in the lowered position and to clear the said operating plate in the raised position, an operating rod for actuating the machine, a convex segmental member fixed to, and co-axial with the pivot of, the guard device, a projection on the operating rod continuously engaging the rim of said segmental member and preventing the operation of the rod in every position of the guard device except the lowermost and safety position, and a notch or the like in the rim of the segmental member located so that in said safety position of the guard device the said projection on the operating rod can pass into the notch and the operating rod can then be actuated to set the machine in operation JAMES ALEXANDER THOMSON NAPIER. 

